Safety-brake for hoisting devices.



PATENTED NOV. 19, 1907. G. A. ARMINGTON.

SAFETY BRAKE FOR HOISTING DEVICES.

APPLIoATIoN FILED J1N.15, 1907.

GEORGE A. ARMINGTON, OF WIOKLIFFE, OHIO.

SAFETYfBRAKE FOR HOISTING DEVICES.

No. s713552.`

Specification of Letters Patent.

Patented Nov. 19,1907.

Application tiled January l5. 1907- serial No. 352.?81-

To all whom it may concern.'

Be it known that I, GEORGE A. ARMING- TON, a citizen of the UnitedStates, residing at Wiekli'ile, in the county of Lake and'State of Ohio,have invented a certain new and use# ful Improvementin Safety-Brakes forHoistingDevices, of which the following is a full,

clear, and exact description, reference being had to the accompanyingdrawings.

This invention relates to hoisting devices and it has particularreference to a safety brakewhich is applied thereto for the purpose ofsustainingthe load and for providing against the too rapid lowering ofthe same, the brake being so constructed that it automatically arreststhe load and holds .the

same until the mechanism is positively driven in a reverse direction, bywhich operation the load is lowered. l

In the accompanying drawings forming a part of this application, Figure1 is a View, artly in sectionand partly in elevation, of a oistingdevice having my automatic safety brake applied thereto. Fig. 2 is atransverse section'taken through Fig. 3, substantially on the line 2-2of that figure, and Fig. 3 is a plan view of the brake, the upper partof the inclosing casing being cut away in order that the brake mechanismmay appear. j

In Fig. 1, lrcpresents the outside casing or framewithin and upon whichthe hoisting mechanism is contained or mounted.y This frame is suspendedfrom a suitable support, as a trolley, by means of a hook 2 andconnections 3 between said hook and the frame. The frame is providedwith a projecting table orv support 4, upon which is mounted the drivingmeans, which, as shown in the drawings, is an electric motor 5 haring anarmature shaft Keyed to this shaft is a small pinion 7, which mesheswith a gear S that is keyed to the hub 9, of a pinion 10, which pinionis loosely journaled upon a shaft 1]. 'lhis shaft is mounted at its lefthand end in the casing 1, and, toward its right hand end, in atransverse web or partition l2 of the casing. The pinion 1() meshes witha gear 13 that is keyed to a shaft 14, said shaft being parallel with'the shaft 11 and being journaled in the same parts of the frame.Secured tothe shaft-14 is a pinion 15, said pinion meshing with a gear'lthat is secured to, or cast-integral with, the hoisting drum 17. 'Thehoisting cable 18 is wound upon this drum and has one of its endssecured thereto,1said cable thence passing about a sheave 19 for thehook 20, to which hook the load is to be applied. From this sheave thecableis suitably secured to a verticallyv extended strut arm 21, saidstrut arm eing pivoted to the casingl 1 at a point 22. As will be seenfrom Fig. 2, the cable is attached to said strut arm at a point 23between the ends of said arm and toward the upper end thereof. l/Viththe exception of the manner of attaching thc cable to the strut arm, thehoisting mechanism thus shown is one only of a great many forms to whichmy invention may be applied, and it has beenv thus dcscribed for thepurpose of showing the manner in which my safety brake may be employed.in connection with devices of this character.

The brake is shown in detail in Figs. 2 and 3, and in section on asmaller scale in Fig. 1. .From the latter figure it will most clearlyappear that the gear 8 -is provided with an annular flange 24 projectingfrom one side thereof, in connection with which the coiled brake band 25is adapted to o )erate. Ollie end of this brake band is secured to the uper end of the strut arm 121 through the me ium of a connecting rod 26,said rod being threaded at its inner end in order that it may be screwedinto an enlarged member 27 on the end of the brake band. The rod ,isalso screw threaded at its opposite end for the purpose of receiving anut 28, which connects it with the strut arm, and for also receiving anut 29'inside of the casing 1, said latter nut being adapted to engagewith the casing and thus prevent the load from setting the brake withtoo great force. The end of the brake band, opposite that to which issecured the member "27, is provided with an angle plate, or othersuitable form of projection 3i), and a similar angle late. or

'projection 31 is secured to the brake and intermediate its ends. Aspring 32 .connects the two angle iron projections thus described, saidspring being normally under sullicent stress to pull said projectionstogether I or setting ,the brake. spring is attached directly to itsrespective projection, while at the opposite end the spring is connectedto a cylindrical member 33 in which is swivcled a bolt b4, said boltbeing pivoted with a nut 35 for engagingthe other projection,wherebyfthe tension oi' the spring may be adjusted.

Projecting inwardlyirom the casing 1 arc angular lugs 36 and 37, saidlugs extending At one of its ends the coiled brake band for frictionallyengaging said flange, stationary stops projecting from the casing, meanson said ,brake band for engaging with said stops, a'hoisting cable, and

`connections betjweensaid hoisting cable and `brake band, asecondprojection intermedi- -ate the ends of said brake band,l itationary '.stops between said projections,

' cable, and connections between said hoisting aehoisting cable and thebrake band, whereby the weight of the load on the cable will normallytighten said band, thev construction being such that when the member isdriven in one direction, one of said projections will engagel With itsstop to .loosen the band and when the member is driven in the oppositedirection, the other projection may engage with its stop to again loosenthe band sufficiently to permit the load to be lowered withoutunnecessary friction.' 6. In a hoisting device, a casing, a driven gearin said casing, a flange -on said gear, a coiled brake band forfrictionally engaging said flange, a projection on one end of said brakeband, a second projection intermediate the ends of said brake band,stationary stops on the casing and extending between said projections, ahoisting cable, and connections between said hoisting cable and thebrake band, whereby the weight of the load on the cable will normallytighten said band, theconstruction beingsuch that, when the gear drivenin one. direction, one of 'said rejections will engage with its stop tooosen the band and, when the gear is driven in the opposite direction,the other'projection will engage with its stop to again loosen the bandsufficiently to permit the load to be lowered without unnecessaryfriction.

7. In a hoisting device, a hoisting drum, gears for driving said drum,an annular flange on one ofsaid gears, a. brake band coiled about saidflange, a cable having one ofv its ends attached to the drum and its ojosite end attached to one end of said bra (c and, a projection on theopposite end of said brake band, a second projection on the brake bandintermediate the ends thereoffa spring` connecting said projections andtending to lgrew the same together, and stationary sto ps et'ween saidprojections.

8.. In a hoisting device, 'a hoisting drum,

gears for driving said drum, an annular flange on one of said gears,- abrake band coiled about said flange, a cable having one of its endsattached to the drum and its op posite end attached. to one-end of saidbrale band, a pro iection on the opposite end of said brake band, asecond projection on the brake band intermediate the ends thereof, aspring connecting said projections and tending to draw the sametogether, means for adjusting the tension of said spring, and stationarystops between said rojections.

9. In a hoisting c evice, a hoisting drum, gears for driving said drum,a flange on one of said gears, a brake band coiled about said flange, arod secured to one end of the brake band, a pivoted strut arm having itsfreeend connected to said rod, a stop on said ^rod for limiting itsmovement in one direction, a cable connectingr the drum and the strutarm, a projection on the end of the brake band opposite said rod,a'second projection intermediate the ends of the band, a coiled springconnecting said projections and tending to draw them together, andstationary stops between said projections, the construction being suchthat when the gear having the flange is turned in one direction, the.stop on the said rod will hold the end of the band to which it isconnected while the friction on the `flange will loosen the band, andwhen the said gear is tu ned in the opposite direction, the saidprojection on the end of the band will engage with its stop, and themovement of the flange will again loosen the band therevabout so as 'topermit the load to be lowered rod, a stop `on said rod for limiting itsmovement in one direction, a projection on the end o i the brake bandopposite said rod, a second projection intermediate the ends of theband, a coiled spring connecting said projections and tending to drawtlfem together, stationary :tops between the said projections, and meansfor adjusting the tension on said spring, the construction being suchthat when the gear having the flange is turned in one direction, thestop on the said rod will hold the end of the band to which it is conynected, while the friction, on the flange will j .loosen the band, andwhen the said gear is turned in the opposite direction, the saidprojection on the endof the band will engage with its sto and the'movement of the flange will again oosen the band thereabout, so as topermit the load to be lowered without unynecessary friction.

In testimony whereof, I hereunto allix my signature in the resence oftwo witnesses. i

GE RGE A. ARMINGTON. Witnesses:

` S. E. FoU'rs J.,B. HULL.

